Heat exchanger



April 30, 1946. c, H', KOPER 2,399,357

HEAT EXCHANGER Filed Oct. 16, `1943 2 She@11s-Sheet', 1

Invention, Charles# lfgper.

April 30,*1946. l c. H. KOPER 2,399,357

HEAT EXCHANGER Patented Apr. 3Q, i-Y i i H. Koper, "il F. SturtevantCompany,

n., Hyde lark,

Application ctober 16, 1943, Se No. 506,539

e claims.

This invention relates to heat exchange units and relates moreparticularly to circular air heaters. v l

Heet exchange units such as so-called unit hesters or down lclslstheaters comprise -ilnned tubes through which steam or hot water iscirculated, and motordriven fans which force air over l the tubesurfaces and into the space to be heated. Such units have beenunsightly, have required more material than is necessaryD have had airpassages in which air turbulence occurred and were not adapted forecient operation-with propeller fans. Y

- This invention provides a heat exchange unit which is more emcient,less expensive and has a better appearance than prior units.

A feature cf this invention resides in the provision oi' a plurality ofconcentric circular finned coils into which oppositely disposed, alignedheadersconnect. the axes of the headers lying in a plane extendingdiametrically through the common centerl of the coils.

whereby when the unit is located with the axesoi' the headers in ahorizontal plane, the coils extend at`slight angles to the horizontal sothat condensate will drain rapidly therefrom.

Another feature of the invention resides in vio side facing Fig. 3 ofthe drawings.

supporting a fan motor at the inner ends of the air is moved through theunit without turbulence.

Objects of the invention are to improve the appearance, utility andeihciency of heat exchange units and to decrease their cost.

The invention will now be described with reference to the drawings, ofwhich:

. i is an elevation view oi' an mbled unit embo 1;- w. this invention:

Fis. 2 is a view similar to Fis. 1 but with the air deecting shuttersremoved;

3 is a sectional view along the lines 3 3 of Eis. l;

his. e is e plan view looming downwardly upon the two sheet metalstampinss which enclose the unit and which provide the air guidingshroudl detail View illustlm 119W the tubes of each coil are pitched withreference to the headers for facilitating drainage of condensate;

vFis. 6 is an enlarged detail view illustrating how the shutter housingis supported from the unit, and

Fig.- 7 is a view oi an assembled unit mounted Afor vertical airdischarge and illustrates how theA uniti may besupported and how theconnecting ypiping-is arranged. c

Referring rst to Figs. 2 and 3, the two aligned pipes l@ and il aresupply'and return headers respectively for the plurality of concentriccircular coils i2. The supply pipe it is perforated at a plurality ofspaced points along one of its sides, the right hand side facing Fig. 3of the drawings. All of the coils l2 except the inner vmost one havecorresponding perforations and are attached to the pipe it by brazing or`welding as. illustrated byFig. 5, with the respective periorations inalignment whereby the pipe I@ may serve as a supply header for supplyingsteam or other fluids into the coils it. The innermost coil it connectsinto the opposite side of the header it.

The pipe il is perforated similar to pipe l@ but along the'opposite sidethereof, the left hand The coils if have corresponding perforations andare attached to thepipe il with the respective 'perforations inalignment whereby the pipe il serves as a. return header.

It will be observed that all of the coils Ir except the inner one arepitched with l t to the common axis of the pipes it and il so that whenthe unitis mounted for vertical discharge as illustrated by Fis. 7. theportions of the coils l2 connected to the supply header pipe l0. will heabove the portions thereof connected to the 'resilient 'mountings lewhich preferably are of the type illustrated by the K. G. Beckett PatentNo. 3,801,818 which issued Nov. 10. 1942. Air

The outer end of the pipe Il has the Tiitting il screwed thereon. Thesupply pipe 20 is screwed Yinto the iitting Il and extends at rightangles to the pipe It. The supporting hanger 2l is screwed into theiitting Il in alignment with the pipe I and serves to suppo the unitfrom an overhead suspension.

The outer end of the pipe i l has screwed thereon the T-fltting 22 whichin turn, has the supp/ly pipe 23 screwed therein at right angles to thepipe Il. The plug 24 is screwed into the tting 22 in alignment with thepipe Il and is removable to permit a return pipe to be connected to thetting 22 when the unit is mounted for vertical air delivery asillustrated by Fig. 7.

The sheet metal stampings 25 and 28 enclose the assemblies described inthe foregoing and are attached as lby the rivets 21 to the cylindricalband 28 which extends in contact with the inner surfaces of their outerwalls.

The inner walls 23 and 30 ofthe stampings are cylindrical and extend inalignment to form a shroud extending completely through the unit.

They are perforated at 3| for receiving the inner end of the hanger 2|and are similarly perforated to receive the outer ends of the pipes loand I I.

The shutter housing 32 is attached to the outer vportion of the stamping28 by the straps 33 which overlap the outer ends of the portions of thehousing in contact with the stamping 2B and which are attached to thestamping 26 by the bolts 34.

The shutter housing 32 has a cylindrical discharge wall 35 which is inalignment with the cylindrical walls 29 and 30 which were previouslydescribed. It will be observed that the walls 29, 30, 'and 35 are inalignment and form a continuous shroud enclosing theheat exchange coilsand the fan and extending from air inlet to air outlet. Prior units ofthis type have had many cavities and breaks which have caused airturbulence resulting in nome and loss of eiciency.

The shutters 36 are mounted on the rods A3l, the ends of which arerotatably mounted in the bearing clips 38 which are attached to thehousing 32 by supporting the beam 42 centrally from the overhead support43. 'I'he pipe 23 would have the cap 44 screwed thereon and the plug 24would be removed from the T-iltting 22 and the pipe 48 would be screwedinto the fitting 22 to serve as the fluid return. To permit the plug 24to be removed and the pipe 45 substituted. the stampings 22 and 23 wouldhave a knock-out washer 46 (see Fig. 3X in a perforation through whichthe plug 24 is to be removed.

While one embodiment of the invention has been described for the purposeof illustration, it should be understood that the invention is notlimited to the exact arrangement illustrated as modificationsl thereofmay be suggested by those skilled in the art without departure from theessence of the invention.

What is claimed is:

1. In a heat exchange unit, a pluralityof concentric circular coilsformed from hollowA heat exchange tubes, and a pair of aligned headershaving a common axis extending diametrically across said coils, one ofsaid headers being located at one side of the center of said coils andhaving one of its sides connecting with the tube forming the outermostof said'coils at one side of the center thereof, the tube forming theinnermost of said coils being connected to the side of said headeropposite to' said one side, and the other of said headers being locatedat the other side of site to said one side of said one header',connecting with said coils.

, 2. In a heat exchange unit. a plurality of concentric circular coilsformed from circular hollow tubes, and a pair of'aligned circularheaders extending diametrically across said coils, said tubes at oneside of the center of said unit being located on one side oi' one ofsaid headers and connect ing'therewith at said one side thereof, and atthe other side of the center of said unit being located on the oppositeside ofthe other of said headers and connecting therewith at saidopposite side thereof.

CHARLES H. KOPER.

